Dayton made a statement Tuesday evening with their 79-65 victory over VCU. Taking a closer look at the game at Dayton Arena the first thing to notice is the offensive efficiency. The Flyers posted a 111 while VCU checked in at 92. What is offensive efficiency?
In simple terms it is points per possession. VCU averaged .92 points per possession to the 1.11 of the Flyers. For the sake of having good round numbers at our disposal, offensive efficiency is points per possession per 100 possessions. In simple terms, points per possession times 100. Now, what constitutes a possession?
Dean Smith devised the points per possession metric decades ago during his assistant coaching days at Air Force Academy. For years, an offensive rebound started a new possession. The last twenty or so years tempo free advocates decided an offensive board extended a possession not started a new one. So a possession ends on a made field goal or free throw, missed shot rebounded by the opposition or turnover.
The formulas:
Possessions = ((FGA + (FTA * .475) – OR + TO))
Points per possession = Points/possessions
Offensive efficiency = Points per possession X 100
Why the .475 multiplied by free throw attempts? Each free throw trip, in an ideal scenario, is two shots. We are calculating the number of trips to the line. Now the problem is teams miss the front end of one and one and to allow for the trip to the line, the attempts are multiplied by .475 rather than .50. That multiplier was devised by stat guru Dean Oliver. If you chart possessions long hand you find the multiplier is a good 95% accurate.
These two teams contested a 71 possession game. No surprise as VCU will pressure and get opponents into a faster pace. The efficiency of Dayton, 111 was outstanding, the visiting Rams at 92, below average. From a numerical standpoint you want to hit 100 or higher on offense. Naturally it is important for your defense to keep your opponent out of triple figures.
Tempo free numbers, especially possessions and efficiency, give a better indication of a team’s offense or defense. One team may allow 55 points a game but not really be a good defensive team if they walk the ball up the floor average 50 possessions a game. Their defensive efficiency would be 110.
On the other hand a team allowing 70 points per game in 80 possession ‘track meets’ would have a defensive efficiency of 88 and prove to be a more efficient defensive team. The following is a chart of the top five teams in offensive efficiency going into play on January 15. Conference games only are factored in and thank you to kenpom.com for the numbers.
Dayton | 115 |
Duquesne | 107 |
St.Bonaventure | 103 |
Richmond | 100 |
Davidson | 100 |